Door latch



March 1958 G. L. WILKS 2,825,593

DOOR LATCH Filed May 25, 1955 5 Sheets-Sheet 1 G L. WlLKS March 4, 1958 DOOR LATCH 3 Sheets-Sheet 2 I Filed May 25, 1955 INVENTOR' G. L. WlLKS 2,825,593

DOOR LATCH 5 She e ts-Sheet 5 March 4, 1958 Filed May 25, 1955.

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United States Patent 7 DOORLAIICH 'Geolfrey L.Wilks,:-Billingshurst,?England Application May 25yl955j-SerialNos 511,000 Claimspriority,application'Griit Brltain -May' z'l,1954 2 (chasm-46 Although applicable for use generally the spur latching device farming the subject of "the presenrinvemien has been "designed primarilyftorusei -eennectien with the do'ors "of vehicles. 'Withthe'us'e of improved draught excluding "seals in caniremen with the hour at motor vehicles ditficulty is often 'xpe'rierieed "in closing and latching such doors especially when e -\iv'indovil's "are closed and "the "chief object"ofthe'jihveiitionis toevolve a door latching device withwhich'the'do'dr esn a lpsed quietly without slamming and with aminimum'df'e'fiort on the part of 'th ope'r'ator.

A door Iatchin'gHevice in adcordatice'Withthepfeseht invention and intended particularly forus'eifdonfiection with the doors f motor vehicles" ificltids, "a ffo'r co-oper'ating witha 'p'egfor 'its equiv-ales: i th'er'fsaid jaw or peg being as'sociatedwith the dodrandtliebther 'e'ein'ponen B in "associated 'j'with "a metrpan, sprin urged toggle link or equivalent mechanism 'nio'vable through a dead centre pd'sitien'as allilfif "figdgifiht "of the jaw'andpe'g or a n additio riallpr'o'fuberafice during closin'g'movemeht 0f the demand an drawin the. jaw 30 and-peg together into'intei'lo'cl'r ing engagememahdthe door into'its-fully cldSdLfiOs'itidn.

Movement of the toggle link or equivalent'riie'chaiiis'm initially through 'a' dead 'ctit'rel'positionto stress, its 'associated spring may be. performed' either by operation of "the door'handle in'the process "of opening thedooror alternatively -by initial openingmovement of the door itself, the former arrangement being rererais1y emfployed.

Referring tothedrawings: 1 I

I Figure 1 illustrates r the door latching device in rear elevation; I I

Figure -2-is a sectional side elevation; r 0

'Figure 3 is a sectional side elevationillustrating the toggle lever mechanism and its assdciatedparts;

Figure 4 is a plan view;

Figure 5 'isan elevational view-ofthe complete mechanism as fitted to a vehicle door and looking-rom-the interior of'the vehicle; v I

Figure 6 i is a fragmentary sectional view illustrating one of the outside door handles'and' assoeiatedaparts,

-The door latching device; illustrated -ha's been designed for inclusion in a motor vehicle door -thedevicebeing operated in; an opening sense directly -by-- means of-an outside handle and indirectly through the mediumof a second handle located within-the vehicle.

The device includes two main supportingzplates Land 2 which are'spaced apart and-carryfixed bearing members-3v and 4 of the knife edge=type with which-engage components-5 and"6,-component-' 5 being carried=by a #Piiif'Of spaced Jinks 7. -Gdmponent 6, the-lowr end of which terminates in a knife edge for co operating with component 4, has associated with it a coiled compression spring '8, the upper 'part of coiiipofieilt fi"being in the form of a rod *9,"-its-upper" extremity: sliding in a bearing membenlfiipivotally associated at 11 with thespair of fiat faces 12 aud13,"the"'point wherethey intersecrbein feiigageable by-a"knife'ed'ge"14 onhal'ing rrietiib'erm to Iirnit angular movement "of i the toggle link f mechanism, "Thisis cla'rly-shown-in Figure Bdhejiarts Whereshown :2 by chain ii'ott'ed lines'being in"their loaded position from "whichrp'osition "they can be moved with a minimum of ifo'rt through a dead centre position, .the coiled coms-pression springlflbenfcoming into operation to move the 5 "tQ'g'gle links into'the 'full lineposition. The manner in "whrenimevemem o f'the togglelinkmechanism is brought about will be described more fully in a 'laterpart of the description. Rigidly associated with components and links .7 is a lldkifig. jaw -1'5 Which-co-operates with a peg '16 carried by afixedpai t di the vehicle body, such as for example, a 'door .-'pi1la'r. 'The'paw1 5-isshaped toengage and enclose thespeg I6 over approximately half its circumference. Ithe'jaw including two spaced-limbs 17 and 18, limb "18 being jslightly'longer-than limb I7for apurpose hereinafter described. :A'ssu'mingthat lthe component parts of the 'toggle'link, mechanism have been moved into their 'loaided positionas indicated by chain dotted lines in Fig- "ure 3, on theYdoor being moved towards its closed posi- 0 "tion, limb-'18 will-engage the fixed. peg'16, thereby causing the jaw-and liriks7 to pivot aboutthe knife edge'3 o'ver'the 'dead 'centreaposition of the toggle link mechanism, the/spring S- then taking charge to move the jaw '15 a'n'd togglef link components into the full line position shown in Figure-'3 thus eflecting final closure movement off' th'e door. It willbe appreciated that limb 17 when ii lbved into thefull line. position will effectively resist opening-movement of the door, but to prevent any possibility of "thedoorbeing opened except by operation of "the'haridleQit-is proposed to provide locking mechanism 'whi'ch is -'show'n-clearly'in'FiguIeZ and takes the form "of arplate 19spivoted at 20 to carrier plate 1, plate 19 being provided with ratchet teeth21 which co-operate with a pawl lzrpivoteditorplatel at 23 and urged into its operative position by imeausof a helical tensionspring 24. Plate 19 is=formed-with a slot :25 in which slides aipin likerprojection 26'f0rming a continuation .of bearing member10 and knife edge '14, thepin projecting 0 through an=arcuate slot i27 formedin carrierplate 1. :As will be seen clearlyifromYF-igure :2 which shows the door lat'ching device in-itsllocked door closed position, pawl 2-2 has engaged oneiof the teeth 21 and pin 26' has enteredthe lower end of slot 25 out of which it cannot move without pivotal movement of. plate 19 being permitted. Consequently the toggle link mechanism will be "maintained in the 'full line position shown. inFigure 3 with the lockingtjaw 15in operative engagement with the. pin 16,-thereby maintaining the door.-securely in its closed position. I

The door latching device includes an additional safety device in the formofapivoted catch28 which trails when engaging and co-operateswith a striker plate29 on a fixedrpart of the vehicle, the catch being urged into its operative projected position by means of a coil spring It 30. A further fixed plate'31 is mounted on arfixedipart of the vehicleunder which a radius on' the top of-the jawrides in the locked position, -thus preventing movernent of the door due to the cammingaction of thev pin. Thisv'projection also provides vertical location'for the door. "The mechanism,,provided for opening ithe door and loading 'the'toggle-li-nk mechanism will now be described. Car'rier plate'll has associated with it bearing lugs 34,35 "and "36 in"'wh'i'ch 'a' vertically positioned spindle 37 is mounted for limited angular movement. -The spindle'3'7 '"h'as'fr'eely' mounted on 'its' 'upper" end" ach'annel shaped ibracket38 (Figs. 1 and'2),"whilst"alug"39"on spindle 37 cai'r'iesan upstanding pin 40 "which" passes through an arcuate' shaped slot "inthe lowe'r'p'ar't' 38aof the bracket, a" "es':iiled sp ring i'l encircling theupper end-of spindle 37 and servin te return the outsidedoer handle-42m ns normal position shown in Figure 6. The outside door handle 42 is connected with bracket 38 by means of a single bolt 43 passing through a hole 43a in the bracket and consequently movement of the outside handle .42 in an opening sense will, when the extremity of the arcuate slot in bracket 38 engages pin 40, cause spindle 37 to be moved angularly about its longitudinal axis.

Spindle 37 carries at its lower end a cam face 44 which co-operates with projection 45 on the pawl 22 to move the pawl out of engagement with the ratchet teeth 21 as a result of angular movement'of spindle 37, thereby disengaging the pawl from the ratchet teeth to permit of opening movement of the door under the action of either the outside handle 42 or the inside handle 46 (see Figure The spindle 37 carries a lug 47 having a pin 48 which enters the slot 49 (Fig. 4) in a link 50, the latter being pivotally connected at 51 to the catch 28. It will be appreciated that the spring 30 will normally urge the catch 28 into its operative position, but on the latter striking the striker plate 29 on the vehicle body the catch will first be forced back, this being possible by the pin and slot connections 48 and 49, the catch then moving into its operative position under the action of its associated spring when the door is fully closed.

Pivotal movement of the locking jaw 15 to cam the latter out of engagement with fixed pin 16 is brought about by engagement of a lever 52,'which is secured to spindle 37, with one of the links 7, the extremity of the lever 52 passing through a slot 53 'in carrier plate 1 into engagement with the link. -In this way the toggle link mechanism will be moved from the full line position through a dead centre position into the chain dotted line position shown in Figure 3 in which position the locking jaw can disengage itself from the pin 16 and allow the door to be fully opened. By virtue of the pin and slot connection between the outside door handle carrying bracket and pin 40, return movement of the handle will not bring about any return rotational movement of spindle 37 and consequently the toggle link mechanism and jaw 15 will remain in the chain dotted line position,'that is to say, ready to assist closure of the door if the jaw 15 is re-engaged with the pin 16.

To open the door from the interior of the vehicle the usual inside handle 46 is provided which is connected by means of a system of links 54, 55 and double ended lever 56 with pin 40. In Figure 5 the door is indicated by reference numeral 57 and the fixed part of the vehicle by reference numeral 58.

Although the faces 12 and 13 co-operating with the faces of the knife edge 14 may be sufficient to limit angular movement of the toggle link mechanism, other means may be provided for this purpose. For example, a stop member 59 may be carried by one or other of the carrier plates 1 or 2, or the slot 60 formed in carrier plates 1 and 2 may be so dimensioned that it restricts that pivotal movement of that part of the locking jaw 15 indicated by reference numeral 61 which projects through carrier plate 1 via the slot 60.

It will be appreciated that by providing the plate 19 with a number of ratchet teeth provision is made for locking the door against opening movement even though the locking jaw 15 and pin 16 have not for any particular reason fully engaged. Such an arrangement is also useful in compensating for any faulty fitting of the device, or structural defects of the door which may have arisen during course of manufacture which tend to force the door open to an extent which might neutralize the closing action of the look.

In the construction hereinbefore described arming of the toggle link mechanism is consequent upon movement of the outside or inside door handle and opening movement of the door in its initial stages. Such arming, however, may be effected not as a direct result of movement of the handle. but as a result of hinging opening movet. "accuses ment of the door. In such a case the toggle link mechanism may be arranged adjacent the door hinges and in this case movement of the toggle link mechanism over a dead centre position into its armed position may be brought about by means of a cam, links or other mechanism associated with the door, the toggle link mechanism being in this case connected with the locking jaw by means of a link or other remote connecting member.

It will be appreciated from the foregoing description that door slamming will be unnecessary, the toggle link mechanism taking charge to complete the closing movement once the limb 18 on the locking jaw has contacted the pin 16.

By the employment of knife edge bearings it is possible to employ a very heavily loaded toggle mechanism which at the same time can be moved through a dead centre position with a minimum of force. Furthermore, it will be appreciated that such knife edge bearings will be located in a relatively inaccessible position and by virtue of their construction will operate satisfactorily without the necessity for periodical lubrication.

I claim:

1. A door latch device intended particularly for use in connection with the doors of motor vehicles including a locking jaw for cooperating with a peg or its equivalent, either said jaw or peg being associated with the door and the other component associated with a fixed part such as the vehicle body, said device comprising a support, a pair of spaced pivots on said support, 'a spring urged toggle link mechanism mounted on and between said pivots, a locking jaw fixed with one link of said toggle link mechanism and swingable therewith, means on said support and engageable with said toggle link mechanism for locking said mechanism in its beyond center position in which the door is closed to retain the door closed, a handle, and means connecting said handle with said locking means and said toggle link mechanism and operative upon opening movement of said handle for unlocking said locking means and moving said toggle link mechanism through dead center to disengage said jaw and peg and open the door, whereby said spring urged toggle link is movable through a dead center position as a result of engagement of the jaw and peg during closing movement of the door for drawing the jaw and peg together into interlocking engagement and the door into its fully closed position, said handle being connected through the medium of a rotatable spindle journaled on said support and carrying a lever engageable with the toggle links to move the latter through a dead center position and the jaw out of locking engagement with the pin, said positive locking means including a pawl and ratchet mechanism, the pawl being moved out of engagement with the ratchet by a cam carried by said spindle upon initial movement of the handle in an opening sense, and said ratchet comprising a pivoted lever having a slot formed therein which co-operates with a pin on the toggle links, the pin and plate being maintained interlocked when the pawl is in engagement with any one of the ratchet teeth. a

2. A device as claimed in claim 1 including a spring urged catch pivotally mounted on said support for cooperating with a striker plate and withdrawable by operation of the door handle through a crank on said spindle and a link having connections with said catch and said crank, one of said connections being a pin and slot connection.

References Cited in the file of this patent UNITED STATES PATENTS 1,447,148 

